Italian to English Tech/Engineering Mechanics / Mech Engineering

Please can you help. I am translating an Italian document into English which is about mechanical engineering. I am struggling to find an English translation for 'morzatore', it's in the context of 'distanziale morzatore'. Does anyone know what this is? I am aware that 'distanziale' is a 'spacer'. The document type is a report and the wording appears in a table.

Many thanks